Populations Terms and Definitions

Birth RateThe number of live births per 1,000

population (people) in a given year.

Death RateThe number of deaths per 1,000 population

(people) in a given year.

Life ExpectancyThe average number of additional years a

person of a given age could expect to live if current mortality trends were to continue for the rest of that person’s life. Most commonly cited as life expectancy at birth.

Replacement Level FertilityThe level of fertility at which a couple has

only enough children to replace themselves, or about two children per couple.

Total Fertility RateThe average number of children that would

be born alive to a woman during her lifetime if she were to pass through her childbearing years conforming to the age specific fertility rates of a given year.

Zero Population GrowthA growth rate of zero, achieved when births

plus immigration equal deaths plus emigration.

B + I + D + E = 0

Infant Mortality RateNumber of deaths of infants under 1 year old

per 1,000 live births

Demographic TransitionThe historical birth and death rates from high

to low levels in a population. The model consists of 4 stages.

Stages of Demographic Transition

Stage 1: Pre-Industrial(not common)

 

Equation 

 

High birth rate + high death rate = little growth 

 

Fact 

High birth rates and high death rates = no great population growth 

 Fact

 

Countries have very basic -living standards-little education or health care-Food supply is erratic -little family planning 

 

Example 

Very rural Africa and Asian communities/villages 

 

Example 

U.S. before colonization 

Stage 2: Transitional

Equation  

High birth rate + high death rate = little growth 

 Fact

 

There are a lot of births, but the death rate has decreased (20/1,000 infants who die). 

 Fact

 

Population increases because more infants are surviving. 

 Fact

 

Reason for less people dying = -health care -improved sanitation-more transportation and medical care. 

Fact  

There’s a slight modernization in health care & that raises people’s living standards & life expectancy. 

 

Example 

Most African countries and India 

Example  

When U.S. was colonized 

Equation High birth rate + high death rate = little growth

 Fact Fact FactFact 

ExampleExample